(loosely) A contradiction in terms. Historically, an oxymoron was a paradox with a point, where the contradiction seems absurd at first glance, and yet is deliberate, its purpose being to underscore a point or to draw attention to a concealed point.
By far the most massive planet in our solar system, Jupiter features giant hurricanes, auroras, abstract artistic cloudswirls, and maybe even a solid core. It also protects Earth by gravitationally clearing the solar system of asteroids and comets.
Jupiter has the largest mass of any planet in Earth's solar system, but mass alone doesn't determine gravity. Its pull exists between any two objects with mass, and its strength is determined by their separation distance as well as their masses, according to Newton's Law of Gravity.